Sleepy? Your memory may be impaired
October 17th, 2012
09:32 AM ET

Sleepy? Your memory may be impaired

Everyone has had one of those days where a night of choppy or short sleep leads into a morning of mental haze. New research presented at the Neuroscience 2012 conference suggests that sleep deprivation might be worse for you than you think.

For starters, sleepiness in the elderly could be an indication of Alzheimer's risk, says Andrew Ward, researcher at Massachusetts General Hospital.

Ward and colleagues did a study involving 84 elderly adults without memory problems, ranging from age 66 to 87. Researchers gave them a questionnaire about how likely they were to fall asleep during various daily activities, as a way to measure sleepiness. They also measured brain activity using functional magnetic resonance imaging (fMRI).

Researchers found that the sleepy study participants tended to show less coordinated activity in the default mode network, brain regions that are active when the brain is resting and are involved in introspection.

This suggests that people with bad sleep may be more susceptible to Alzheimer’s, but "we need to do more research to see if this is actually true," Ward said. The next step would be to follow the participants over time to see who develops Alzheimer's in the long term. The study also suggests that improvements in sleep may restore network connectivity - but again, further investigation is necessary to make more substantial conclusions.

Elderly people generally sleep fewer hours and wake up more frequently during the night than their younger counterparts, Ward said. And reports from Alzheimer's caregivers suggest that people with worse sleep have more severe memory impairments.

A second study also emphasized the importance of getting a good night's sleep. Hengi Rao, a researcher at the University of Pennsylvania, presented an experiment involving sleep deprivation in a laboratory. Participants spent four nights in the lab as researchers controlled their number of sleeping hours, gave them memory tests and scanned their brains (doesn't that sound fun!).

The 22 healthy adults slept nine hours the first night, went 24 hours without sleeping, and then spent two nights gaining recovery sleep. Their brains were scanned after nights 1, 2 and 4.

After sleep deprivation, researchers found that participants showed less connectivity between the default mode network and the hippocampus, a region of the brain essential for memory. After recovery sleep, however, their brains showed the same activity as after that first night of nine hours of sleep. Their performance on memory tasks was correlated to the activity in these regions.

"It’s critical to obtain recovery sleep after sleep loss and avoid chronic sleep deprivation" in order for the brain to restore the integrity of this neural network, Rao said.

How much sleep loss are we talking about? Ted Abel of the University of Pennsylvania discussed a study he's involved with using mice. Of course, mice are not perfect approximations for humans, but may give some insight into what's going on in the human body. It turns out that mice show memory impairment after being deprived only about three hours of their normal sleep, which translates into 20% of their daily total.

If animal models are to be believed, memory strengthening can be affected in a human who sleeps six hours instead of eight hours, this study suggests.

Bottom line: Getting a good night's sleep is important for memory.

More from CNN Health: Acting out dreams while asleep

soundoff (39 Responses)
  1. George

    Surprize surprize surprize !! Lack of sleep causes memory problems !! Who paid for this "study?"

    October 17, 2012 at 10:29 | Report abuse | Reply
    • PraiseTheLard

      You're right... we should stop funding all studies... after all, there are never any unexpected outcomes, are there?

      October 17, 2012 at 11:42 | Report abuse |
    • George

      Replt to Praisethe L - Didn't say THAT, but a study to learn whether lack of sleep causes memory loss is ridicuous.

      October 17, 2012 at 13:39 | Report abuse |
    • Paul

      You're both right! If there were studying to see if sleep deprivation causes impairment in memory then that's already been proven. We have known that for a long time. (And memory returns when you have a good night's sleep). If they were specifically checking to see if it causes Alzheimer's, though, well then that would be something we didn't know.

      October 17, 2012 at 15:25 | Report abuse |
    • O-coma

      You're all wrong! We already know that Romney himself injected Alzheimer's into steroid sources in key swing states!

      October 17, 2012 at 16:41 | Report abuse |
    • woodie

      Dead people have bad memories. But that's a different kind of sleep.

      October 17, 2012 at 18:53 | Report abuse |
    • George

      Paul, Paul, Paul – It is an election year. Why are you saying anything of reason? Don't you know that is not allowed this year?

      October 17, 2012 at 19:35 | Report abuse |
    • Mike

      Surprise surprise, someone with a simplistic view of science made the predictable comment "Who is funding this?"

      October 18, 2012 at 00:25 | Report abuse |
    • Gizmo

      Paul, has it really been proven already, or has it been correlated? These two do not mean the same thing.

      I'm not sure why some of you think this study is a waste of time. Just because we have studied it once before doesn't mean it does not n eed to be done again. If I were to study something that hasn't been studied before and publish the study, does that mean no one else in the world can perform the same study because they/we will learn nothing from it and because I have already performed that study? You don't study something once and that's it. Tat would assume that the other studies are correct and have no fallacies.

      Science is NOT a waste of money, no matter if th study has been done or not.

      October 18, 2012 at 09:23 | Report abuse |
    • danny


      October 18, 2012 at 10:55 | Report abuse |
    • lifewithjamie

      It's called science people. Facts must be established and supported before they can be built upon. I think the information is very interesting and useful.

      October 18, 2012 at 22:15 | Report abuse |
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  2. D. LeJeune

    This article is so true. I am living proof. After suffering, what I felt was, severe short-term memory loss, I finally asked my doctor for a sleep study test. It was found that in an 8 hour night (480 minutes), I stopped breathing over 200 times. I was prescribed a sleep apnea machine which I use religiously not only for night-time sleep but for naps as well. If it were not for this machine, I would not be sleeping at all. Memory has improved greatly; however, I still have lapses where I cannot think of the correct word to say (which unnerves me!) or I say the wrong word for something (and this happens on a daily basis!) like instead of saying "take off your shooes", I will wind up saying "take off your feet".

    October 17, 2012 at 10:30 | Report abuse | Reply
    • Paul

      Shoes... feet... close enough! Only, the later would be a bit hard to put back on. Hopefully the D. in your name means doctor!

      October 17, 2012 at 15:28 | Report abuse |
  3. Leticia Cuevas

    This article will be a great help for my psychology homework.

    October 17, 2012 at 10:55 | Report abuse | Reply
  4. Seth Reddington

    After reading this article, the first thing that comes to my mind is (yawn)....... wait.... what was it about?

    October 17, 2012 at 12:20 | Report abuse | Reply
  5. R. LeBlanc

    Yawn... I can't remember having memory problems.

    October 17, 2012 at 12:29 | Report abuse | Reply
  6. tonysgirl1959

    Sorry, but ths article made me sleepy...

    October 17, 2012 at 12:29 | Report abuse | Reply
  7. Portland tony

    I wonder how our ancient ancestors ever survived? Reason would indicate that those who slept longer were more prone to being attacked by whatever or whomever were preying on them. Whether it be wild animals or an enemy tribe. Hence, the advice: 'sleep with one eye open' kept :you alive a little longer!

    October 17, 2012 at 13:01 | Report abuse | Reply
  8. karek40

    I read the article, "If animal models are to be believed, memory strengthening can be affected in a human who sleeps six hours instead of eight hours, this study suggests." I think the author meant to say memory strengthening can be affected by getting 8 hours of sleep instead of 6 or perhaps I did not understand the article which may mean I need more sleep.

    October 17, 2012 at 14:07 | Report abuse | Reply
  9. Pompous Doctor

    I'm so excited, I might not beat my wife tonite.

    October 17, 2012 at 14:25 | Report abuse | Reply
  10. Paul

    >>The study also suggests that improvements in sleep may restore network connectivity...

    Try an ethernet cable instead of sleep!

    October 17, 2012 at 15:18 | Report abuse | Reply
  11. Minnie Mouse

    Getting a good nights rest is important for memory. Adequate sleep is also vital in your every day life functions. Getting up at the same time everyday is what I personally feel is the most beneficial. Your not doing your body any good if your getting to little sleep or not enoug sleep. This allows to where your getting the same amount sleep everyday. Works great for me and you also get more time in your days. If you sleep in 2 to 4 hours just because it's the weekend, that's time lost. Time is precious, so take advantage of every 24 hours that you are given.

    October 17, 2012 at 16:54 | Report abuse | Reply
  12. Minnie Mouse

    Type O. Your not doing body any good if your getting to little or to much sleep.

    October 17, 2012 at 16:57 | Report abuse | Reply
  13. eroteme

    Wonderful! We have been blessed with guidance from anoher 'researcher'. What in the world would we do without them!

    October 17, 2012 at 18:16 | Report abuse | Reply
  14. Bill

    I hardley slept a wink last night. I was going to make a comment here, but I can't remember what I was going to say.

    October 18, 2012 at 08:34 | Report abuse | Reply
  15. JLS639

    The fashionable term at the Society for Neuroscience 2012 was "connectivity," which is ultimately what both of these studies were about. I would be cautious before getting too excited about these, though. There are numerous problems with the fMRI technology as it stands now. It is really too bad in light of all the fascinating research and breakthroughs I saw in are understanding of vision, ion channels, dietary fat and neuron function, central control of metabolism and what allows someone to make fast judgements calls acurately. I saw one poster showing a fascinating relationship between ion channels involved in olfaction (sense of smell) and weight gain and diabetes on a high fat diet. There was some great sleep research, as well.

    This highly preliminary fMRI with amibguous data where they can data mine a few results gets all the attention.

    October 18, 2012 at 08:40 | Report abuse | Reply
  16. Laerrus

    Usually means I smoked too much pot too early in the day...

    October 18, 2012 at 09:39 | Report abuse | Reply
  17. GAW

    I have a photographic memory....I just forget to put in the film. I guess I need more sleep.

    October 18, 2012 at 09:53 | Report abuse | Reply
  18. GeorgeD

    I was awake all night one time, could not sleep. I went to work and as soon as I got out of the car, my coworker flagged me and told me that I forgot to wear my pants! Then it dawned on me that lack of sleep will truly affect my memory.

    October 18, 2012 at 10:06 | Report abuse | Reply
  19. Paula D.

    Wow...what incredible insight!! Who would've thought! Thank God for science! Please let me know how I might contribute large sums to fund any of the equally important and relevant research programs: 1) Swallowing Large Marbles a Possible Choking Hazard for Infants; 2) Used Kitty Litter Not Recommended for Consumption as Healthy Alternative to Vegetables; 3) If You're Traveling to Pluto, You Will Need Warm Clothing; 4) Gasoline Found to Be the Recommended Fuel Source in Most of Today's Vehicles; 5) Alcoholism Linked to Alcohol Consumption in Adults; 6) Findings Reveal that Majority of Atheists do Not Attend Church on a Regular Basis; 7) Pork Rinds linked to Obesity, But Only When Consumed; 8) Saliva Causes Cancer But Only When Consumed in Small Amounts Over a Long Period of Time; 9) Credible Link Found Between Rock Concert Attendance and Hearing Loss; 10) Daily Sun Exposure Contributes to Greater Risk of Skin Cancer.

    October 18, 2012 at 10:07 | Report abuse | Reply
    • JLS639

      Did you read more than the headline? How about possible connections between lack of sleep, daytime sleepiness and Alzheimer's? How about mapping exactly which areas of the brain are affected by sleep loss, and which ones retain normal function? You cannot make up fake headline mocking the actual research, can you?

      The research outlined by the article had some serious limitations. I would explain them to you, but it would be a waste of time since you only read the first line of what I wrote, anyway.

      October 18, 2012 at 10:22 | Report abuse |
  20. Kaitlin

    I understand the correlation between Alzheimer's and sleep; as well how lack of sleep effects your memory. Although this may be true you can also look at your methods of memorization. For example when using your short term memory: look at the following letters then close your eyes and try to remember the sequence u a v f c i d b d s a i. More than likely you did not remember the order. Now look at the letters in this sequence: d v d f b i u s a c i a. Now this sequence there was no trouble remembering, this is called chunking- the grouping of related items together into a single unit. This is just one of several methods you can use if struggling with memorization.

    October 21, 2012 at 22:07 | Report abuse | Reply
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      October 23, 2012 at 22:52 | Report abuse |
    • Khalil Laghari

      Thanks for information . We User Experience Researchers also use memory techniques and brain data to develop applications with lesser cognitive load. These memorization techniques will definitely help. Any book or article suggestion please?

      July 17, 2013 at 18:25 | Report abuse |
  21. Regie

    I agree with this, sleep is very important. It also makes you feel rejuvenated.

    November 14, 2012 at 13:48 | Report abuse | Reply
  22. Gabrielle

    I am doing a project for my health class where i need to find a blog about a question that we are researching, and i was wondering If you knew anything about how taking naps on a regular basis can affect a teens regular sleep cycle. Please respond asp, Thanks.

    December 1, 2012 at 05:18 | Report abuse | Reply
  23. truongmhu

    Very good

    October 2, 2013 at 09:14 | Report abuse | Reply
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